化学汚染物質の迅速検出のためのラマン分光アッセイ強化フィルターベースの表面
Summary
製造や化学汚染物質（ すなわち、農薬フェルバムと抗生物質アンピシリン）の検出のためのラマン分光（SERS）アッセイ強化フィルタベースの表面を実行するための手順が提示されています。
Abstract
We demonstrate a method to fabricate highly sensitive surface-enhanced Raman spectroscopic (SERS) substrates using a filter syringe system that can be applied to the detection of various chemical contaminants. Silver nanoparticles (Ag NPs) are synthesized via reduction of silver nitrate by sodium citrate. Then the NPs are aggregated by sodium chloride to form nanoclusters that could be trapped in the pores of the filter membrane. A syringe is connected to the filter holder, with a filter membrane inside. By loading the nanoclusters into the syringe and passing through the membrane, the liquid goes through the membrane but not the nanoclusters, forming a SERS-active membrane. When testing the analyte, the liquid sample is loaded into the syringe and flowed through the Ag NPs coated membrane. The analyte binds and concentrates on the Ag NPs coated membrane. Then the membrane is detached from the filter holder, air dried and measured by a Raman instrument. Here we present the study of the volume effect of Ag NPs and sample on the detection sensitivity as well as the detection of 10 ppb ferbam and 1 ppm ampicillin using the developed assay.
Introduction
表面増強ラマン分光法（SERS）は、ナノテクノロジーを用いて、ラマン分光法を組み合わせた手法です。貴金属ナノ表面における検体のラマン散乱光の強度が大幅に局在表面プラズモン共鳴により増強される。1銀ナノ粒子（銀NPS）その高い拡張能力をはるかに最も広く使用されているSERS用基板である。今まで2 Ag NPの様々な合成方法が開発されている。3-6のAg NPは、その感度および/ または機能を増強するのに有効なSERS基板として単独で使用、または他の材料及び構造と組み合わせることができる。7-11
SERS技術は、食品や環境試料中の様々な微量汚染物質の検出のための偉大な能力を実証している12は伝統的に、SERSのサンプルを調製するための2つの一般的な方法があります：。。溶液系と基板ベースの方法は、13 ソリューションベースのメトdは、サンプルと混合するNPコロイドを使用しています。次にNP – 分析物複合体は、遠心分離を用いて回収し、乾燥後のラマン測定のための固体支持体上に堆積されます。基板ベースの方法は、通常、事前に作製した固体基板上に液体試料のいくつかのマイクロリットルを堆積させることによって適用される。14が、これら2つの方法のいずれもが、試料容量の大量のために有効かつ適用可能です。 SERSアッセイのいくつかの変更は、フィルターシステム15-21またはマイクロ流体デバイスの組み込みの統合などの音量制限を、克服した。21-24修正されたSERSアッセイは、化学汚染物質を監視するための感度と実現可能性に大きな向上を示しています大規模な水サンプルインチ
ここでは、農薬フェルバムおよび抗生物質アンピシリンの微量を検出するために製造およびシリンジフィルターベースのSERS法の適用の詳細なプロトコルを示します。
Protocol
Representative Results
Discussion
このプロトコルにおいて重要なステップの一つは、均一のAg NPは一貫性のある結果を得るための鍵である銀のNP合成、です。加熱時間及び前駆体の濃度を正確に制御しなければなりません。このAgNPs製剤の平均サイズはゼータサイザーで測定した80ナノメートルである（データは示さず）。別の重要なステップは、塩濃度及び凝集時間を正確に制御しなければならない塩の集合体です。小さい?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
This material is based upon work supported by the U.S. Department of Homeland Security under Grant Award Number 2010-ST-061-FD0001 through a grant awarded by the National Center for Food Protection and Defense at the University of Minnesota. Disclaimer: The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Department of Homeland Security or the National Center for Food Protection and Defense.
Materials
| Ampicillin | Fisher Scientific | BP1760-5 | N/A |
| Ferbam | Chem Service | N-11970-250MG | 98+% |
| Silver nitrate | Sigma Aldrich | 209139 | 99.0+% |
| Sodium citrate dehydrate | Sigma Aldrich | W302600 | 99+% |
| Sodium chloride | Sigma Aldrich | S7653 | 99.5+% |
| EMD Millipore Durapore PVDF Membrane Filters | Fisher Scientific | VVLP01300 | 0.10 µm Pore Size, hydrophilic |
| Polycarbonate Filter Holders | Cole-Parmer | EW-29550-40 | 13 mm diameter |
| Analog Vortex Mixer | Fisher Scientific | 02-215-365 | N/A |
| Nutating Mixers | Fisher Scientific | 05-450-213 | N/A |
| DXR Raman spectroscope | Thermo Scientific | IQLAADGABFFAHCMAPB | Laser power: 1 mW Exposure time: 5 s |
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